It's sort of like a fan's wet dream come true. Sort of.
So what is PXZ? It's basically Super Robot Wars but without the robots. And with the combat system of Super Robot Wars Exceed Saga, in which you chain combos on screen, while calling in supports from team members near you or from solos attached to you.
So why is it good? Because it lets you play with many familiar characters from many different settings at once. Instead of Marvel vs Capcom, think of this as Everyone vs Everyone and as a strategy RPG instead of a fighting game. How often do you get to see characters like Sakura interact with Ryu or Ken? Outside of fanfiction that is. However, the choice of which characters are included are somewhat strange. Like why is Sakura Taisen's 4 main character included but not Glycine from ST3? Or Sumire? Or why is Yumeria EVEN in the game?? Holy crap, that's an old and forgotten game.
Also, your characters fight in pairs and while some of the pairs make sense; ie. Ryu and Ken, Yuri and Estelle, some really really seem strange. Like Dante and Dmitri, wtf is up with that? Or Frank West and Hsien Ko. Again, wtf?
However, it also suffers from a lot of flaws as well. The first would be the graphics, which are really dated even for a Nintendo handheld. I can't really complain about the sprites since that's a conscious decision to use them and that's pretty much how most SRWs are really. But some of the character portraits are pretty flatly colored and really could have done with some better drawing.
I mean, those are some pretty telling differences in art quality right there. Ignoring the girl from Yumeria; because seriously, who cares about Yumeria? The character portraits on the right have much better shading than the ones on the left.
Also, I would have preferred a more SRW style system of fighting, where you choose your actions from a list and it just acts them out instead of the combo system we got in PXZ. But again, I understand it's a conscious design choice because that's how the previous games were like. But still, it missed out on a lot of cool dramatic move cinematics, which you only get to see now once you charge your power bar to 100% and more.
That aside, my other real gripe is with the battles. Which are basically kind of boring after a while. Mostly because all the game does is spam waves of enemies at you. Waves of enemies which aren't even that hard to defeat and can usually be one-shotted. Either the game needs to get harder or it needs to present me with more mission options that can be fulfilled in ways other than 'kill everyone else on screen and you win'. Although to be fair, even actual D&D with DMs trying to railroad you have issues with avoiding that scenario. Which is why I have an issue with the fighting system of the game. If you're going to spam endless waves of minions at me, at least make it so that I don't have to repeat the same combo for everyone of them. With the SRW style, I could just click an attack and it'll execute without me needing to do anything else. In this, I have to combo. And it gets tiresome after 20 times when you're doing it against the same enemy. And battles need a speed-up button because enemies take damn long to move.
There's also the fact that certain teams are obviously much better than the others. The main character duo of the game? Not so great due to their weird attacking patterns. Ryu and Ken however are amazingly strong. So are Chun-Li and Morrigan, Haken and Kaguya etc. Granted, this is going to happen in any cross over game but the difference in strengths can be pretty overwhelming at times. The Sakura Taisen characters suck by the way, which is pretty sad.
So why would you play this game? Because it's a fun mindless waste of time that manages to tug at all the right strings of nostalgia and which will actually make you want to replay the old games. I actually felt like digging out my old Sakura taisen games after playing this. But other than that, it's an average game. It could have been much better but what saves it is really the fact that it has shit loads of cross overs in it.
Also, hopefully if enough people buy this game, it'll convince the company to start translating more japanese games into english. Starting with ACE ATTORNEY INVESTIGATIONS TWO AND SRW OG SAGA: EXCEED. Seriously, wtf would you translate the first game and not the sequel? What kind of cruel bastards do that???